Lord Howe Island – a botanist’s paradise

Lord Howe Island – a botanist’s paradise

Two of our botanists recently spent a week collecting ferns on Lord Howe Island. They were adeptly guided by Lord Howe Island museum curator Ian Hutton and joined by Daniel Ohlsen from the Royal Botanic Gardens Victoria. Lord Howe Island is a nature-lovers’ paradise with much of the island protected in reserve and mammal pests recently eradicated. Our fern findings will be detailed in a future blog post but here Lara Shepherd and Leon Perrie discuss the natural history of Lord Howe Island and introduce some of its flowering plants.

Photo from the air of four people standing together on a rocky outcrop. Out behind them is an island surrounded by the sea. There are rocky cliffs at the far end of the island.
Photo of the fern-collecting team from the northern end of Lord Howe Island. Photo by Ian Hutton

Lord Howe Island is a small island (less than 15 km2) located 700 km northeast of Sydney.

The island is an old shield volcano that formed around 7 million years ago but has since eroded to about 1/40th of its original size. Two steep remnant volcanic peaks dominate the skyline in the southern part of the island – Mt Gower (875 m) and Mt Lidgbird (777 m).

The two high peaks of an island with a sandy beach in the foreground. It is dusk and there are purple and blue colours in the sky.
The two highest peaks on Lord Howe Island Mt Gower (right) and Mt Lidgbird (left). Photo by Leon Perrie

Lord Howe Island was one of the last places in the world to be settled by humans. It was first sighted in 1788 by British sailors en route from Sydney to Norfolk Island. The first permanent settlers arrived in 1834 bringing pigs, goats and cats. Mice arrived in 1850 and rats reached the island following a shipwreck in 1918.

These introduced animals wreaked havoc on the island leading to the extinction of at least nine bird species and two plants (it is likely that there were also extinctions of smaller animals, such as invertebrates and lizards).

Inspirational predator control

In 1981, 70% of the island was made a permanent park preserve and a year later the island was made a UNESCO World Heritage site. Feral cats and pigs were eradicated in the 1980s and Aotearoa New Zealand hunters shot all the goats in 1999.

Twenty years later rats and mice became the target of an eradication programme. These initiatives have already had a positive impact – the endemic Lord Howe woodhens (Gallirallus sylvestris), relatives of our weka, were reduced to only 15 birds in 1980, thought to be a result of feral pigs.

Following pig eradication, their numbers slowly increased to around 250 by 2007/2008. However, after the commencement of the rodent eradication, woodhen numbers increased four to five-fold. This suggests that rats were also having a big impact on the woodhens, possibly competing for food.

The Lord Howe woodhen, a medium-sized brown bird walking on the grass.
The Lord Howe woodhen, a relative of our weka, is a common sight on the island. Photo by Lara Shepherd

A recovering biota

It will be interesting to see how the plants and animals recover following the recent rat and mouse eradication, especially the less visible critters such as invertebrates.

Already a cockroach and four snail species, all thought to be extinct on the main island, have been rediscovered. The lack of rodents is also having a positive effect on the native forest with seeds that were previously eaten now germinating in abundance.

Unfortunately, the weeds on the island are likely to also rebound following the rodent eradication. A weed eradication programme has been in place since 2004. It is based on the Aotearoa New Zealand Department of Conservation’s programme for Raoul Island in the Kermadec Islands.

We noticed that the weeds were less dominant on Lord Howe Island than on our recent trip to Norfolk Island, despite the much more challenging terrain for the weeders, as seen in the photos taken by Lara and Leon below.

Unique plants of Lord Howe Island

The plants of Lord Howe Island have affinities to those of Australia, New Caledonia, Aotearoa New Zealand, and Norfolk Island. Despite being a much smaller island than Norfolk Island, Lord Howe Island has many more native vascular plant species (around 240 on Lord Howe Island vs around 180 on Norfolk Island) and more endemic vascular plants (105 on Lord Howe Island vs 46 on Norfolk Island).

This is probably because Lord Howe Island is older, closer to Australia, and has a greater range of habitats. Many of the endemic species occur in the mossy cloud forest on Mts Gower and Lidgbird.

A sunny day with a mountain top shrouded in white cloud. The rest of the mountain has green bush growing on it.
The summits of Mt Lidgbird (pictured) and Mt Gower are often crowned in cloud, allowing cloud forest to thrive. Photo by Lara Shepherd

Four genera of plants are endemic to Lord Howe Island (found nowhere else). Three of these genera are palms and contain four species. The most well-known is the kentia palm (Howea forsteriana), which is the most popular cultivated palm in the world. The export of kentia palm seed began around 150 years ago and was once the biggest export from the island.

A woman in dark trousers and a turquoise top and blue hat is walking away from the camera on a road with palm trees growing on both sides.
Lara walking in the Kentia palms (Howea forsteriana), Lord Howe Island. Photo by Leon Perrie

Pumpkin tree (Negria rhabdothamnoides) is a member of an endemic genus and the only member of its family to form a tree, reaching 8m in height. Interestingly, it is distantly related to African violets and the New Zealand gloxinia/taurepo (Rhabdothamnus solandri).

A close up of a big yellow five-petalled flower growing of a large-leafed plant.
The vibrant orange flowers of the pumpkin tree (Negria rhabdothamnoides). Photo by Lara Shepherd

A puzzling distribution

Despite its name, the Lord Howe wedding lily (Dietes robinsoniana) is a type of iris. Its occurrence on the island has bamboozled botanists – the five other species in the genus only occur in southern Africa. DNA research indicates that it arrived in Lord Howe by long-distance dispersal.

A white flower growing on a long-leafed plant. It has five main petals with yellow stripes on three of them and three smaller petals in the centre.
Lord Howe wedding lily (Dietes robinsoniana). Photo by melange, via iNaturalist. CC-BY-NC

Aotearoa New Zealand relatives

The hotbark tree (Zygogynum howeanum) gained its common name because its bark (and leaves) is hot to chew. It is a distant relative to Aotearoa New Zealand’s horopito (Pseudowintera colorata), which also has a hot peppery taste to the leaves.

A big-leaved plant with medium-sized white flowers and yellow berries in the centre.
Hotbark (Zygogynum howeanum). Photo by johnporter47, via iNaturalist. CC-BY-NC

There are over 50 species of Coprosma in Aotearoa New Zealand, making it the centre of diversity for the genus. Lord Howe has six species, including stinkwood (Coprosma putida), whose leaves and fruit smell terrible, and Coprosma huttoniana, named for Ian Hutton, our guide on the island.

A broad-leafed shrub growing close to the ground.
Coprosma huttoniana. Photo by Lara Shepherd

The mountain daisy (Olearia ballii) is endemic to Lord Howe Island, where it is common on the higher mountains. It is a relative of New Zealand’s tree daisies.

A green shrub that has leaves that look a bit like the rosemary herb with white daisy flowers on it.
Mountain daisy (Olearia ballii). Photo by Leon Perrie

Lord Howe has 12 orchid species. Some species, like the onion orchid, are shared with Aotearoa New Zealand or Australia. The drooping cane orchid (Dendrobium moorei) is endemic to Lord Howe and has large flowers compared with its Aotearoa New Zealand relative winika (Dendrobium cunninghamii). It only grows on the mountains above 400m elevation.

A flash photo of a green long-leafed plant hanging down a bank. It has white drooping flowers in a bunch.
Drooping cane orchid (Dendrobium moorei). Photo by Lara Shepherd

Lord Howe Island has two endemic species of mountain rose, which are in same genus as our rātā and pohutukawa (Metrosideros). They are both potentially at threat from myrtle rust which has been detected twice on the island but eradicated both times.

A tree that is growing out of the side of a hill with many of it's roots exposed. There is more forest behind it.
One of the mountain rose species, Metrosideros sclerocarpa, has striking bark. Photo by Lara Shepherd
A spindly branch with small clumps of leaves in rosettes and bright red flowers.
Mountain rose (Metrosideros nervulosa). Photo by dhfischer via iNaturalist. CC-BY-NC

Lignum vitae (Sophora howinsula) is closely related to and looks very similar to Aotearoa New Zealand’s large-leaved kōwhai (Sophora tetraptera). Seeds of the ancestor of lignum vitae likely floated to Lord Howe Island in the last few million years.

A close-up of a branch with green leaves and yellow flowers that are trumpet like, similar to the New Zealand kowhai tree.
Lignum vitae (Sophora howinsula). Photo by panyan, via iNaturalist. CC-BY-NC


Ian Hutton for guiding us and sharing his wealth of knowledge about Lord Howe ferns (and other plants, birds, fish as well as the history of the island).

Jenny and Brian Solomon for gifting us the guidebook on Lord Howe ferns, which was written by Ian, and inspired us to research these fascinating plants.

Lord Howe Island resident Tim Solomon kindly organised a source of newspaper (it is a scarce commodity on the island), enabling us to press our fern specimens.

The Lord Howe Island Board allowed us to stay at the Research Facility and approved our fern research.

Three books about plants, marine life, and ferns of Lord Howe Island are laid out in a row, face up.
Some of the many books written by Lord Howe Island museum curator Ian Hutton. Photo: Lara Shepherd


  1. This is a great post – I really enjoyed it! Keep up all your excellent work – scientific, conservation, and reporting!

  2. Keep up the fabulous work, Kiwi botanists, conservationists and rodent eradicators!! If I were 50 years younger, I’d love to join you!! I always take time to read Te Papa’s blogs, especially those involving conservation issues. Thank you for the excellent articles & photos. Dr. Angela Kay Kepler, Maui, Hawaii.

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